Electrical conductivity of individual polypyrrole microtube

Conducting microtubes (0.4－0.5μm in outer diameter) made of polypyrrole (PPy) doped with p-toluene sulfonic acid (PTSA) were synthesized by a self-assembly method. We report the electrical conductivity of an individual PPy microtube, on which a pair of platinum micro-leads was fabricated by focused ion beam deposition. The measured room-temperature conductivity of the individual PPy microtube was 0.29S/cm, which is comparable to that of template-synthesized PPy micro/nanotubes. The temperature dependence of conductivity of the individual microtube follows the three-dimensional variable-range hopping (3D VRH) model.